C / circumductus
noun

circumductus

gen. circumductūs · gender masculine · decl. 4th
circumduco.
The circumference of a figure
The circumference of a figure, Quint. 1, 10, 43.—*
Motion in a circle; a revolution
Motion in a circle, a revolution: orbium, Macr. Somn. Scip. 2, 1, 5.